Originally Posted by
koiman1950
As long as you have enough thread depth on the bulkheads, I would definitely want to have both liner and plywood sandwiched between the bulkhead pieces. That's how my qtank was done. I also used GE Marine5200 to seal around the bulkhead on the inside of the pond. I used a "no-niche" skimmer with the pipe going through the side wall as well. I did this pond back in 1998 and it's been watertight the whole time! I would suggest you get the appropriate size hole saws for cutting through the plywood, then cut the liner out making it about 1/4"-3/8" smaller diameter. This will allow a bit tighter seal around the threaded male side as you insert it from inside the pond out. For that sized pond, I don't see a need for a mid-water pick-up. This pond is temporary, and based on around 1250-1400 gal in size, depending on the filtration you plan to use, you can use a single pump fed from the BD and skimmer alone to get enough gph to handle a turnover of twice/hr with no problem.